Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds real context beyond that: no personal details are returned because the route sends none, amounts are in ordinary currency units not paise/cents, and it is workspace-scoped with no account id. Return-shape disclosure is a useful addition.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads the purpose and the enumerated contents, then moves to usage triggers and caveats. The first sentence is a dense run-on list, but every clause carries distinct information about what is returned, so little is wasted.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description compensates by spelling out the returned fields (code, link, counts, commission rate, earnings buckets, recent sign-ups with date and plan) plus the currency-unit and privacy caveats. An agent has everything needed to call and interpret it.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Only one parameter and schema coverage is 100%, so the schema already documents limit fully (default 20, max 50, newest first). The description adds nothing about the limit parameter, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Names a specific resource (the workspace's referral and affiliate standing) and enumerates exactly what it exposes: referral code/link, open and signup counts, conversions, commission rate, earnings breakdown. This is unmistakably distinct from siblings like account_usage or stats_overview.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives concrete trigger phrases ('what is my referral link', 'how many people have joined through me', 'how much have I earned', 'when can I withdraw'), which is strong positive guidance. It does not name an alternative tool or an exclusion, though no close sibling exists to disambiguate against.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.